1. Field of the Invention
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having an auxiliary electrode for reducing a discharge starting voltage between discharge sustain electrodes and a method for driving the same.
2. Description of the Related Art
FIG. 1 shows the structure of electrodes of a conventional surface discharging type AC plasma display panel. As shown in FIG. 1, a data electrode 5 is arranged at a rear substrate 2. Discharge sustain electrodes comprised of a scanning electrode 3 (which may be referred to as a xe2x80x9cY electrodexe2x80x9d, hereinafter) and a common electrode 4 (which may be referred to as an xe2x80x9cXxe2x80x9d electrode, hereinafter) are arranged in parallel to cross the data electrode 5. A dielectric 7 is coated on the discharge sustain electrodes 3 and 4. The discharge sustain electrodes 3 and 4 are arranged in each discharge cell having a discharge space 9 provided by walls 6 (parts marked with dotted line are rotated by 90xc2x0) arranged in strips perpendicular to the discharge sustain electrodes 3 and 4. Bus electrodes 8 for improving the conductivity of the transparent electrodes 3 and 4 are formed on the discharge sustain electrodes, namely, the X electrode 4 and the Y electrode 3 to be arranged around the perimeter of the discharge space.
In the plasma display panel having the above structure, driving an electrode is roughly divided into driving for an address period and driving for a sustained discharge. As shown in FIG. 2, the address period is generated by an electric potential difference (80Vxe2x88x92(xe2x88x92170V)=250V) between the data electrode 5 of the rear substrate 2 and the Y electrode 3 of a front substrate 1. At this time, a wall charge is formed. The sustained discharge is generated by an electric potential difference (140Vxe2x88x920V=140V) between the Y electrode 3 and the X electrode 4, arranged in the discharge cell in which the wall charge is formed. The sustained discharge for displaying a real image becomes a main discharge.
The main discharge generated by the electric potential difference applied between the X electrode 4 and the Y electrode 3, become decreased as time passes, as shown in FIG. 3. This is because the discharge starting voltage for the sustained discharge driving should be generally no less than 160V since the distance between the X electrode 4 and the Y electrode 3 of the front substrate is about 80-100 xcexcm in the electrode structure of the conventional surface discharging type AC plasma display panel. When the discharge starting voltage becomes large, consumption of electric power increases and the rating of a driving circuit becomes larger, thus costing much. Also, an induced voltage is generated in an adjacent electrode, thus causing crosswalk. When the distance between the X electrode 4 and the Y electrode 3 is narrowed in order to reduce the discharge starting voltage, an electrostatic capacity becomes too large. Namely, the discharge starting voltage is lowered as the distance d between two electrodes becomes shorter. However, it has a restriction on lowering the distance d because of an undesirable increase in the electrostatic capacity. It is very important to driving the plasma display panel to reduce the discharge starting voltage without increasing the electrostatic capacity which are parasitic between the two electrodes.
To solve the above problem, it is an objective of the present invention to provide a plasma display panel in which it is possible to remarkably reduce a discharge starting voltage by arranging a thin auxiliary electrode between an X electrode and a Y electrode, maintaining the two electrodes as they are and a method for driving the plasma display panel.
Accordingly, to achieve the above objective, there is provided a surface discharge type AC plasma display panel, comprising a front substrate and a rear substrate which face each other with a predetermined distance, walls for maintaining a distance between the front substrate and the rear substrate and providing discharge spaces, pairs of discharge sustain electrodes arranged in strips on a surface of the front substrate to be parallel with each other, and data electrodes arranged on a surface of the rear substrate in strips perpendicular to the pairs of discharge sustain electrodes, wherein an auxiliary electrode of a predetermined thickness is arranged between each pair of discharge sustain electrodes.
The thickness of the auxiliary electrode is preferably such that it does not increase the electrostatic capacity of the pairs of discharge sustain electrodes.
To achieve the above objective, there is provided a method for driving a plasma display panel comprising a front substrate and a rear substrate which face each other with a predetermined distance, walls for maintaining a distance between the front substrate and the rear substrate and providing discharge spaces, pairs of discharge sustain electrodes arranged in strips on a surface of the front substrate to be parallel with each other, and data electrodes arranged on a surface of the rear substrate in strips perpendicular to the pairs of discharge sustain electrodes, wherein an auxiliary electrode of a predetermined thickness is arranged between each pair of discharge sustain electrodes, comprising the step of applying an auxiliary electrode driving pulse to the auxiliary electrode earlier than the point in time at which the discharge sustain pulses are applied to the discharge sustain electrode pairs.
In the present invention, the auxiliary electrode driving pulse preferably makes the electric potential of an auxiliary electrode equal to the electric potential of an electrode having a higher electric potential among the pair of discharge sustain electrodes when the discharge sustain pulse is applied to the pairs of discharge sustain electrodes and the discharge becomes larger and preferably maintains the electric potential of the auxiliary electrode to be equal to the electric potential of an electrode having a lower electric potential when the discharge is decreased.
In the present invention, the auxiliary electrode driving pulse preferably makes the electric potential of an auxiliary electrode equal to the electric potential of an electrode having a lower electric potential among the pair of discharge sustain electrodes when the discharge sustain pulse is applied to the pairs of discharge sustain electrodes and the discharge becomes larger and preferably maintains the electric potential of the auxiliary electrode to be equal to the electric potential of an electrode having a higher electric potential when the discharge is decreased.